This specification relates generally to pulley systems and, more specifically, to safety mechanisms to address lifting cord failure in pulley systems.
Pulleys are used to lift an object attached to a cord (e.g., a cable, rope, wire, chain, string, or other cord) by translating a downward force applied to one end of the cord to an upward force on the object attached to the other end of the cord. If the lifting portion of the cord happens to be severed or released while lifting the object, a conventional pulley, with no built-in safety system, will allow the object to fall. This type of cord failure can not only cause damage to the object, but also harm those close to the object when it falls.